The present invention relates to a calculation method for packing plural wire materials forming a wiring harness or the like as compactly as possible, a calculation apparatus using the same and a computer-readable recording medium, and more particularly, to a calculation method for packing plural wire materials so as to satisfy conditions under which wire materials are respectively moved, a calculation apparatus using the same and a computer-readable recording medium.
Wire-like structures known as wiring harnesses formed by binding together plural wire materials such as electric wires are provided in vehicles and indoors. The harnesses act to electrically connect electric appliances, electronic components, and so on. In recent years, such a wiring harness has been required to be made as compactly as possible without impairing the electrical characteristics from a viewpoint of improvements of the space efficiency. Concomitantly, it becomes necessary to calculate the most compact wiring harness in the design stage. In the past, however, any specific and efficient calculation method for this purpose has not been proposed.
Accordingly, the present applicant and others have proposed a calculation method in JP-A-2004-127917 to gain information about the outside diameter of a wire cable obtained by binding and packing plural wire materials and information about the positions of the wire materials, using a computer. The wire cable is formed by binding circles corresponding to the cross-sectional shapes of the wire materials into a minimally sized circular form such that the circles do not overlap with each other. This makes it possible to calculate a comprehensive circle when plural circles are bound and packed into a minimally sized circular form such that the circles do not overlap with each other. Heretofore, it has been considered to be difficult to perform this calculation. Note that the comprehensive circle corresponds to the cross section of the wiring harness created by binding the plural wire materials.
In reality, however, electric wires forming wiring harnesses are not limited to single wires, or single electric wires. In addition, as shown in FIG. 4A, there exist composite wires known as twisted wire 8 or flat wire 9. The twisted wire 8 is obtained by twisting together plural electric wires 81. The flat wire 9 is obtained by connecting plural electric wires 91 along a flat plane. Numerals 82 and 92 indicate conductor lines in the electric wires 81 and 91, respectively. Each electric wire forming this kind of composite wire must be packed as a unit. Some electric wires (not shown) are preferably placed more outwardly than other electric wires. Conversely, some electric wires are preferably placed inwardly of other electric wires so as to be surrounded by them. That is, in reality, it may not be possible that electric wires can be moved at will and packed. In many cases, electric wires are restricted to their respective given moving conditions.
However, the method of JP-A-2003-179718 proposes a fundamental technique for binding together and packing plural wire materials into a minimally sized circular form. In this method, conditions under which the wire materials are moved (hereinafter may be referred to as the “movement conditions”) are not established. That is, circles corresponding to the wire materials can be moved at will according to results of calculations for packing.
Therefore, when calculations for packing are performed in a case where composite wires as described above are contained or the locations where the wire materials are placed are specified, it has been impossible to directly apply the method of JP-A-2003-179718. Any efficient calculation method for packing plural wire materials while satisfying movement conditions as described above has not yet been proposed.